Abstract: An analyte concentration monitoring system having network-based communication features which provide a link between an analyte detection system and a centralized computer. The analyte detection system has a processor that calculates analyte concentration in accordance with software executable by the processor. Under certain conditions, the software needs to be updated. Accordingly, when the analyte detection system is connected to the centralized computer, the centralized computer determines whether a software update is needed. If a software update is needed, then the centralized computer conveniently provides the software update to the analyte detection system without intervention from a user.

Abstract: An analyte concentration monitoring system having network-based communication features which provide a link between an analyte detection system and a centralized computer. The analyte detection system has a processor that calculates analyte concentration in accordance with software executable by the processor. Under certain conditions, the software needs to be updated. Accordingly, when the analyte detection system is connected to the centralized computer, the centralized computer determines whether a software update is needed. If a software update is needed, then the centralized computer conveniently provides the software update to the analyte detection system without intervention from a user.

Abstract: A glucose monitoring instrument having network-based communication features which provide a link between patient and practitioner. The glucose monitoring instrument comprises circuitry for communicating data with one or more destination sites on the network which are configured to transmit and receive information to and from the instrument. Instrument measurements are transmitted over the link in addition to information and guidance, to provide increased accuracy, improved program compliance, and patient guidance from a supervisory authority or medical practitioner. In addition, a set of calibration features encourage calibration compliance.

Abstract: A glucose monitoring instrument having network-based communication features which provide a link between patient and practitioner. The glucose monitoring instrument comprises circuitry for communicating data with one or more destination sites on the network which are configured to transmit and receive information to and from the instrument. Instrument measurements are transmitted over the link in addition to information and guidance, to provide increased accuracy, improved program compliance, and patient guidance from a supervisory authority or medical practitioner. In addition, a set of calibration features encourage calibration compliance.

Abstract: The invention relates to an immunoassay cassette useful for carrying out multistage immunoassays in an automated manner. In operation, the cassette assumes different operational positions in which solutions are transferred sequentially across an absorbent pathway containing assay reagents.

Abstract: An assay device and method for determining the concentration of an analyte in a fluid sample. The device includes a porous-matrix reservoir which receives the sample to be assayed, and at least two reaction zones into which sample fluid is drawn from the reservoir. In an embodiment containing two reaction zones, a single-point standard curve which corrects for reduced-signal effects related to loss of reagent activity and linear inhibition effects, is used to determine analyte concentration. In an embodiment containing three reaction zones, a two-point standard curve which corrects for reduced-signal effects related loss of reagent activity and non-linear inhibition effects, is used to determine analyte concentration. Also disclosed is an apparatus which uses the device for automated or semi-automated analyte assay.

Abstract: An assay device and method for determining the concentration of an analyte. Analyte introduced by liquid absorption into the matrix is used to generate H2O2, via an analyte-specific oxidase, and the H.sub.2 O.sub.2 is utilized by peroxidase in the presence of peroxidase to convert a substrate reagent to a colored reaction product. A trapping compound in the matrix competes with the substrate reagent, in the presence of the peroxidase enzyme, to produce a silent reaction product, thus proportionately reducing the amount of signal reaction product generated by a given amount of analyte. Detection of a wider range of analyte concentrations is therefore possible.

Abstract: Method and apparatus for use in determining the concentration of a selected analyte in a body-fluid sample. As the fluid sample is applied to a wettable, absorbent reaction pad, the extent of sample wetting of the pad is monitored by surface reflectance. This surface monitoring is used to control the volume of sample applied to the pad, to prevent overfilling the pad and to allow determination of the final sample volume applied. From the known sample volume and amount of analyte, the concentration of analyte in the sample can be accurately calculated in reaction components, trapping agents, matrix configuration, and analyte tested can be made.

Abstract: An assay device for assaying multiple analytes in a drop-size blood sample. The device includes a sample dispenser designed to distribute a small-volume blood sample to multiple transfer sites, by capillary flow of the blood sample through sieving and distributing matrices which separate blood cells from serum as the sample fluid migrates toward the transfer sites. A test plate in the device carries multiple absorbent test pads, each containing reagent components for use in detection of a selected analyte. The test plate is mounted on the dispenser for movement toward and away from a transfer position at which the exposed surface regions of the pads are in contact with associated sample-transfer sites, for simultaneous transfer of sample fluid from such sites to the pads in the support.

Abstract: A membrane structure is disclosed having controlled capillarity useful in detecting cells in a solution by promoting effective contacting between cells and the membrane surface bearing affinity for selected cell sites. Also disclosed is a mtehod of using such membrane structures to detect particles in solution. One embodiment of the invention is an improved blood-typing device and method. The device may be attached to a blood bag, clamp, stick or the like, to provide a permanent visual record of blood type.

Abstract: Apparatus for accurately transferring liquids for filling or diluting microliter quantities of regents, analytes or cells for bioassays and the like include a vessel having a plurality of troughs for supplying an array of pipettes to effect the transfer. The vessel is automatically indexable on a horizontal table to bring a selected trough into register with vertical movement of the pipette tips. The table is then indexed to bring the tips into alignment with a plurality of microtiter tray wells. In a preferred form the troughs are of different widths to supply differing quantities of liquid to the pipettes for transfer.